DECOY SN // Save up to $1300 on our supernatural E-MTB
$6,499.00
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$3,099.00
$3,299.00
$1,999.00
$2,499.00
$4,999.00
Overview
CORE 5
CORE 4
CORE 3
CORE 2
CORE 1
UNCAGED 13
UNCAGED 14
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Size
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Version
Day in, day out rippers, this is where it's at! JEFFSY CORE 4 is stacked with innovative, performance-focused components and is locked and loaded for unrelenting speed on your favorite trails. Formed from High-Modulus carbon and dripping with high-end parts, this trail bike is an extension of you, and together, you'll unite to dominate any challenge. This CORE 4 spec goes big, harnessing bleeding-edge tech from RockShox and SRAM to bring control and elevate your trail-slaying game in the process.
Hide your loot on all Carbon frames
Putting the rider in focus
Never go thirsty again!
inch
cm
5'0" - 5'5"
5'4" - 5'9"
5'8" - 6'1"
5'11" - 6'4"
6'3" - 6'8"
Crimson Red
Black Magic
This bike has the earliest arrival
All Available Options
Included:
YT Bike Box
Costs nothing, helps a lot – the toolbox contains everything you need to assemble your bike.
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Our High-Modulus carbon crushes it on the trail, offering immense strength, lightweight performance, and an improved ride feel.
1/1
Gone are the days of taping a tube to your frame: Beneath the double-sealed, weatherproof lid lies two water-resistant neoprene bags to keep your payload silent, while a separation wall prevents your goods from getting lost within the frame. Sidewall bonding keeps the cables extra tidy, and for total security, we separated the bottle cage from the lid to prevent unwanted movement.
Tools, check. Spare tube? Check. Why let a mechanical end your ride; use the toptube mounts to ditch the backpack to store your essentials.
For optimal protection and sleek lines, cables are routed almost entirely through the frame. This bike is a mechanic's dream: Uninterrupted internal tubes provide easy, intuitive cable replacement and eliminate noise for stealthy slap-free riding.
This frame is compatible with the SRAM UDH hanger, meaning it can pair with a wide range of drivetrain options, including SRAM Full Mount Transmission rear derailleurs. Sent it too hard? No sweat – these hangers are easily available worldwide.
Stashed neatly into the rear axle, this custom, removable HEX6 tool is always on hand to save the day. The design allows for effortless wheel removal, helping to put you back on track in no time, and is engineered with ergonomics in mind to ensure generous hand clearance. Whether stuck on the trail with a puncture or cramming multiple bikes in the car for a road trip, this tool has you sorted.
Included with JEFFSY is our Thirstmaster 6000 bottle and cage combo. As our go-to solution for rider hydration, this BPA-free bottle has a 620ml capacity to quench even the driest thirst, and the side-load cage is simple to use, even on the move.
The JEFFSY features Rider Centered Geometry, so you can push harder on the trail in total confidence. A roomy reach measurement, slack head angle, proportional seatstay measurements, and a steep, 77-degree effective seat tube work in sync to create a balanced and precise bike. JEFFSY keeps you, the rider, as the focus – It’s your best friend, after all.
Situated at the lower shock mount, the Flip Chip makes it quick and easy to adjust the geometry according to your ride style. This chip is set to low by default but increases the BB height by 8mm and ST/HT angle by 0.6 degrees in the high position. It's your call: Choose high for enhanced agility, precision, and climbing efficiency or low for trail-ripping confidence and a lower center of gravity.
Our V4L suspension technology is award-winning and has seen more than a few podiums in its time. Sensitive off the top, the design provides claw-like traction on loose terrain while remaining supportive through the mid-stroke. The end-stroke ramps up to prevent bottom-out, even on monster jumps, and did we mention the pop? Load up that linkage and let it fly.
Proportional seatstay lengths ensure JEFFSY is perfectly balanced. By keeping the front and rear center in check, the ride character is fast, confident, and predictable, for total control when things get hectic.
Depending on your weapon of choice, your JEFFSY will feature either a carbon or hand-crafted aluminum frameset. Our carbon fiber frames come in two options: High Modulus and Ultra Modulus. Both materials are equally durable and built for rowdy riding, with Ultra Modulus being the lighter choice.
Extensive chainstay and seatstay protection guards the frame from chain slap, while the knobs reduce chain slap noise. All you’ll hear is the adrenaline rushing through your veins and your tires rolling over the trail.
In addition to the double-sealed industrial bearings used, all pivot points are equipped with an additional seal to keep water and dirt at bay, protecting the bearings and extending their service life.
Increased heel clearance to reduce friction caused by the shoes rubbing on the frame while riding.
Silence is the sound of speed. More than just robust protection, the extensive frame guards eliminate unwanted noise, keeping you focused on the trail ahead as you descend like a ninja. JEFFSY even goes a step further: Beneath the bolt-on downtube protector lies sound-deadening foam to keep you cruising through those "Oh sh*t" moments without fear.
Flip Chip Position
low
high
s
m
l
xl
xxl
Jeffsy 29 Core Range Manual - MY2024
PDF | 7.88 MB
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Now in its third iteration, JEFFSY rewrites the rulebook for trail bike performance. No half measures; only Trail Excellence.
29
MX
Not sure if this is the perfect fit? Go ahead and browse more models!
Uphill
Downhill
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